Stephen Sommers is bringing G.I. Joe to the big screen for Paramount Pictures. Following the success of last summer's Transformers, the pressure to bring the 1980's cartoon and comic series to life in a way that is both respectful to the fans, but realistic enough for modern audiences is a significant challenge. Part of that challenge will be casting the right actors, a process that has begun according to Variety.

Sienna Miller (Stardust) is the first actress to be given a role in the film. Although they don't name the character, the description that is given for her is "the film's female lead, described as a raven-haired baroness and sexy femme fatale skilled in espionage." To fans of the series, this is clearly the Baroness, one of the higher-ranked officers of Cobra.

According to a release from Hasbro, the film will follow the "G.I. Joe vs. Cobra" storyline featured in the comics and cartoons of the 1980's. The basic premise involves the Joes, led by Duke in their "fight for freedom wherever there is trouble" against Cobra Commander, The Baroness, Destro and the rest of the Cobra force.

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G.I. Joe is set to begin filming in February, with an August 7, 2009 release date.